Locomotives used for heavy haul, over the rail applications and for passenger applications presently are controlled using a master controller and/or train line signals. A master controller often is a microcomputer, including a processor and a memory device, and operated with software that receives operations data and control signals, and sends command signals to effectuate commands from an operator. The control signals may come from a user- or operator-controlled master control stand that includes three handles extending from the locomotive's master control stand. These are a throttle handle, a dynamic brake handle, and a reverser handle, and each is associated with a respective control device that senses the position of the respective handle and communicates with the master controller by sending control signals.
A throttle control device of the master control stand may have, for example, eight notches of operation for motoring, where the throttle handle may align with any one of the notches at one time. Each notch corresponds to a specific Tractive Effort (TE) and/or power (such as horsepower (HP) or watts) request to the master controller. The amount of TE produced depends on various conditions but is primarily dependent on the speed of the locomotive and/or train including the locomotive. The dynamic brake handle controls, for example, the electric motors that drive the locomotive wheels, to set the motors either in motoring mode to drive the locomotive, or in generator mode, where they will generate power and thereby retard the motion of the locomotive. The power so generated may be directed to a resistor grid on the locomotive, with heat from the grid dissipated externally. Lastly, the reverser handle, for example, may set the direction of torque production of the electric motors to drive the train forward or reverse. The reverser handle also includes a neutral position.
Such system, including the throttle and throttle control device communicating with the master controller, works well for typical over the road, long-haul operations. However, it is less suited for yard operations where the locomotives or trains need to be positioned or where frequent coupling of locomotives and other rolling stock is required. Even the lowest notch setting of a standard locomotive throttle mechanism may provide too much TE or power to effectuate a desired coupling in a yard, resulting in relatively slow start-and-stop advancing to couplings, or undesired forceful couplings that may result in damage or excessive wear. Thus, the current control systems may be viewed to provide for relatively inefficient operations in a yard setting.
There exist switcher locomotives that are designed specifically for slow speed coupling and de-coupling uses in rail yards. Some such switcher cars are designed for radio wave control from a number of control towers in the yard. These radio controlled switcher locomotives may have relatively complex electronics controls, and may be provided with relatively slow speed options for yard operations.
However, this latter type of switcher has various elements and constraints that limit its flexibility and efficiencies, such as with regard to long-haul operations.
Thus there remains a need for more flexible methods and systems for control of locomotives.